So I wanted to add blue blinking 5mm LEDs to my alarm (Karr series 3). The bypass switch and the original crappy red light are housed together and are hooked up with 22 gauge wires from a wiring harness. Can I tap two more Led into these wires without frying something? I know LEDs use very little energy but I'd rather have some input before I do anything.

Thanks.

 

bump, i want an answer on this as well, alarm needs more visibility to bad people so they go break into something else.

 

Sort of reviving an old thread here, but I find the security indicator in the dash of my 11 JKU barely noticeable unlike the flashing beacon in the window on my wifes WJ. I'm planning on adding an aux LED (dummy one) into the plastic trim over the windshield so its visible, but need an easy source of constant +, ignition switched + (preferably only engine run - not accessory) and of course ground. Anybody have a wiring diagram that can shoot me some locations and wire colors?

 

constant+ : center dash panel, right lighter plug
switched+ : center dash panel, left lighter plug
ground: from one of those two other wire...

and it's fairly easy to get access to them, just pry out the bottom panel, pry up the top dash panel over the radio, and 4 screws hold the main panel with the lighter plugs...

take pics and tell us about it... I want to do same mod but would like to tap into the real security LED, not make a dummy, and probably install it left of my manual shifter.

 

Excellent idea, I will post pics when I do it, but mine is a 2011 and only has a switched power outlet in the dash, as my constant outlet is in the center console. Also hoping to find a + source that is ignition only on, not accessory so the light wont flash when in acc position.

 

mmmh, not really... you need an inverter relay.

What you need is:
1x DPST relay (smallest will do... a LED is a very small load!)
1x 12V-rated LED
1x small resistor

You want to wire your LED as per the yellow light in the "power to turn on" circuit; the ignition is playing the role of the "switch" here:

(ignore the green light)

So:
1) tap + wire from constant outlet in console, put in on "30" on the relay.
2) tap + wire from switched outlet in dash, put it on "85" on the relay.
3) tap - wire from one or the other, put it on "86" on the relay.
4) take LED short side (-), put it in line with a small resistor, then on "86" as well to go to ground.
5) take LED long side (+), put it on "87a".
6) cut pin 87, it is worthless here.

Here is how it works:


1) When the key is in the "acc" or "on", it will give current into relay passing from 85 to 86.
The magnet will pull the steel plate and it will no longer contact pin 87a, effectively shutting down your LED.

2) When the key goes back to "off", the current will no longer pass, steel plate will rise and contact will be made with your pin 87a, so LED will light up.


A 30min project, really!
Enjoy!

Mat


P.S.: how to identify LED + and - :

 

That was really well written and correct!

 

Yes, definately excellent write-up. If I was building from scratch this is the way to do it, however I have a Varad LED alarm module, so all I need is switched and constant power plus ground. The circuit in the LED takes care of the rest.

Is there an easily accessable switched + thats not live in ACC position in this general area?

Thanks again!

 

mmmh, your custom module is most probably simply a box with my the same electronic design and 3 wires coming out...
so unless you want your LED to flash while you are in ACC, you should do the suggested taps.

so quick research on that module (http://www.varad.com/option.html) gives:
- red to +12v constant in console
- black to ground in console
- yellow to +12v switched in dash lighter plug
(I do understand that you just want to put a DUMMY, and that you don't want to connect it to the stock alarm, or to a full Varad system, right?)

if you want something really piece of cake, you can use 3 of these and call it a day
http://www.posi-lock.com/posiplug.html

unfortunately I can't tell you which wire color is +12V /ground, haven't took apart my dash yet...


P.S.: 25-30$ for a LED+relay is a bit pricey, but those scanners look nice!

 

so ? have you found your switched source ?